For the first time in a 3 Series model, the 335i Coupe's dual exhaust system runs at both sides of the vehicle - logical, as each contains its own turbocharger turbine and therefore requires extra space. At low loads, a flap channels most gas through one side to reduce low-frequency exhaust "rumble." The 335i Coupe features an air-to-oil external oil cooler mounted in one wheel well as opposed to the N52's coolant-to-oil unit.